Material stitching and guiding apparatus



sheet of 4 R. W. WINBERG vPviATERIALI STITCHING AND GUIDING APPARATUSMarch 25, 1969 Original Filed May 31, 1966 v In www 1 f. 11 5 NN %& 4 Nw$4 G n ....Kn?. L l u ii o N v 0 .&\\ E 4 n QN N .4 s N IU. .mv QN NQrlw l "I o Il! Il. n NQ lm G \N$ Q 4. SPG 4 N\o\ NQ Sx Al N NC Il MNIlm. $4 x Nm. Nw.

March 25, 1969 R. w. WINBERG 3,434,439

MATERIAL STITCHING AND GUIDING APPARATUS BY :g (37 aim March 25, 1969 R.vv. WINBERG 3,434,439

MATERIAL STITCHING AND GUIDING APPARATUS original Filed May :51, 196esheet 3 of 4 INVENTOR.' ,M6/VA@ M ll//frw March 25, 1969 R. w. WINBERGMATERIAL STITCHING AND GUIDING APPARATUS Sheet FIG. 4.

Original Filed May 31, 1966 FIG. 5

INVENTOR @4m/4,@ W. fm/@M6 @Tram/FYI 3,434,439 MATERIAL STlTCHlNG ANDGUDTNG APPARATUS Ragnar W. Winherg, 115 W. Elder Ave.,

This is a continuation of application Ser. No. 553,783, filed May 31,1966.

The present invention relates generally to sewing apparatus, and inparticular to a machine for stitching one or more plies of materialalong a stitch line coextensive with and spaced from the edge of amaterial assembly. Advantageously, the present machine finds usefulapplication in the stitching of superposed pieces of material togetheralong curved or contoured edges, as may be required in the manufactureof a wide variety of articles of manufacture, and in particular in mensand womens wearing apparel.

In various stages of apparel manufacture, it becomes necessary to joinsuperposed pieces of material together along a stitch line which isspaced inwardly from the coextensive edges thereof. Usually, the machineoperator matches up the superposed edges and then feeds the same throughthe sewing machine while continuously guiding the material to assurestitching along a line uniformly spaced from the superposed edges toprovide the required selvages or margins outwardly thereof. Attemptshave been made to modify conventional sewing machines to facilitate thesemi-automatic or completely automatic feed of material thereto tothereby eliminate or reduce the need for an operator in constantattendance. For a wide variety of reasons, which are well understood bythose skilled in this art, such equipment has found only very limitedusefulness and in most instances has been confined to straight linestitching of continuous lengths of material or the stitching of largequantities of an assembly which requires the same repetitive pattern.

There exists a need for semi-automatic or automatic stitching equipmentwhich enables the joinder of superposed plies of material along aprescribed course, whether the same be curved or straight. It would beparticularly advantageous if such equipment could be useful for eithershort or long runs so as to be able, by relatively simple adjustment, tohandle the various stitch lines which are required from day to day in atypical manufacturing operation. For example, in a garment factory, andeven when conned to the stitching of a single type of garment, there areseams which, depending upon the style and size of the garment, will varyin both length and curvature. Even when merely switching from onegarment to another, or from one size of garment to another, differentstitching conditions are presented. For a machine of this type toacquire widespread acceptance, it is essential that the same be readilyadaptable to the new conditions. Of paramount importance, is thecapability of the machine to complete a stitch line which has thevarious desirable attributes of one stitched by a skilled machineoperator.

In copending application Ser. No. 275,297 filed on Apr. 24, 1963, nowabandoned, and copending application Ser. No. 556,535 filed May 20,1966, now Patent No. 3,322,081, the latter application being acontinuation of the former and both entitled Material Stitching andGuiding Machine there is disclosed a semi-automatic sewing machine whichexhibits the requisite capablities for stitching of superposed plies ofmaterial along a stitch line which stitch line closely follows thecurvature of the coextensive edges of the superposed plies and is3,434,439 Patented Mar. 25, 1969 substantially uniformly spacedtherefrom. Such apparatus embodies a conveying and guiding mechanism forbodily advancing the material assembly, be it one or more plies, to awork location while continuously orienting the assembly in accordancewith the contour of the edge along which the stitch line or seam isrequired. The conveying and guiding mechanism includes a conveyor whichis arranged to underlie and engage the material and to advance the samealong a feed path toward the work location. An elongated flexible cammember is arranged substantially along one side of the feed path and isadapted to be secured in a prescribed configuration relating to thecontour of the edge of the material. The cam member is engaged by a camfollower which is movable therealong, with provision for engaging thematerial with the cam follower such that the material is steered inaccordance with the prescribed configuration of the cam member todisplace the material in relation to the feed path while the same isbeing bodily advanced toward the work location by the conveyor. Theflexible cam member is reconfigured from time to time in accordance withthe particular edge configuration and may be changed over by the machineoperator in relatively short order and without undue difficulty.Experience with this type of equipment indicates that still greaterVersatility may be imparted to the equipment if it were possible tosteer the cam follower or clamp by a cam member or track which did notrequire physical resetting each time a different set of stitchingconditions were encountered. The realization of this further desirableattribute would make it a relatively simple matter for a relativelyunskilled machine attendant to almost instantaneously change over fromstitching conditions requiring a given length and given contour to adifferent length and/or different contour. Thus, it would be possible toemploy the same equipment for stitching, in succession and with therelatively short change over time, a curved seam for a sleeve, asomewhat straighter and longer seam at the inside or outside of atrouser leg and the enumerable other stitching conditions which areencountered on a day to day basis in this one field. The versatility andadaptability of the present invention to automating operatorcontrolledand guided stitching equipment will be apparent to those skilled in theart as the instant description proceeds.

It is an obje-ct of the present invention to provide automatic sewingapparatus which realizes one or more of the aforesaid objectives.Specifically, it is within the contemplation of the present invention toprovide a feeding and guiding mechanism which may be operativelyarranged relative to a conventional sewing machine head and permits thestitching of one or more plies of material along a stitch line whichclosely follows the contour of the material edge and is in proximitythereto.

In accordance with an illustrative embodiment demonstrating objects andfeatures of the present invention, a machine is provided for stitchingmaterial along a prescribed stitch line coextensive with and spacedinwardly from an edge thereof which comprises a support. Sewingmechanisms are mounted on the support and include the usualreciprocating needle operable at a stitching location for successivelystitching the material along a prescribed stitch line. The material isarranged forwardly of the stitching location and advanced toward andthrough the stitching location along a normal feed path relative to theneedle, as by the provision of a conveyor. Guide means are engageablewith the material and operable to impart steering motion to the materialas the same is advanced toward the stitching location for displacing thematerial from side to side relative to the normal feed path such thatthe material will be stitched substantially along the stitch line and inuniform spaced relation to the adjacent material edge. The guide meansincludes an elongated guide rail or track projecting forwardly of theneedle and a clamp movably mounted on and guided by the rail. The guiderail is mounted on the support for movement relative to the normal feedpath, with the clamp being engageable with the material contiguous tothe trailing end of the contoured edge when the leading end of such edgeis initially positioned at the stitching location. Means are provided,preferably in the form of photocells, which are responsive to thedeviations of the edge relative to the normal feed path for moving theguide rail in a direction to restore the edge to the proper orientedposition for continuous stitching along the prescribed an-d stitch line.The guide rail is effective in response to its movement to impart acorresponding steering motion to the clamp as the latter is movedtherealong and toward the stitching location to continuously orient andproperly present successive edge-adjacent portions of the material inrelation to the stitching mechanisms for stitching along the prescribedstitch line. In a typical illustrative machine, the elongated guide railis rigid and is mounted on the support for pivotal movement, with thephotocells constantly monitoring the position of the guide rail andpivotally adjusting the same such that the material edge contiguous tothe stitching location will always be in proper relation to the needlefor stitching along the prescribed stitch line.

The above brief description, as Well as further objects, features andadvantages of the present invention will be more fully appreciated byreference to the following detailed description of a presentlypreferred, but nonetheless illustrative embodiment in accordance withthe present invention, when taken in conjunction with the accompanyingdrawings, wherein:

FIG. 1 is a plan view of a stitching machine embodying features of thepresent invention, shown with a typical material assembly in positionfor feed therethrough and with parts broken away and sectioned to revealconstructional details;

FIG. 2 is a side elevational view of the machine;

FIG. 3 is a schematic and diagrammatic representation of the controlsemployed in the present machine, with the controls shown in the restcondition of the machine;

FIG. 4 is a partial showing of the control shown in FIG. 3, illustratingthe running condition `of the machine; and,

FIG. 5 is a partial view similar to FIG. 4 likewise showing a furthercondition of the machine during restoration to the FIG. 3 position.

Referring now specifically to the drawings, there is shown a materialguiding and stitching machine, generally designated by the referencenumeral l0, which is suitable for the stitching together of superposedplies or pieces of materials M having a curved or contoured edge e.Although a single ply of materials is illustrated in the drawings, itwill be appreciated that this is intended to be merely representative ofthe various single pieces or multiple ply assemblies which may bestitched with the present apparatus. Although the sewing machine will berecognized as being a typical lock stitch sewing machine, it willlikewise be appreciated that various types of commercially availablesewing apparatus may be employed in accordance with the presentinvention. Finally, although emphasis is placed herein on automaticstitching for the garment or wearing apparel industry, it will beappreciated that the invention find application in many other fields.

The machine includes a support or frame 12 having a horizontallyextending feed bed or table 14 providing a large work-supportingsurface. Mounted on the support 12 across one end thereof is a sewingmachine, generally designated by the reference numeral 16, which may bea typically `drop-feed lock stitch sewing machine of the typemanufactured by Singer Machine Company. The illustrative sewing machine16 includes a machine body 1S having an upstanding head section 18a andan elongated body section 18b. Extending longitudinally of the machinebody 18 is its main drive shaft 20 which serves to motivate the usualsewing machine mechanisms including the vertically reciprocating needlebar 22 having the needle 24 and the associated bobbin and bobbin racewayand other known machine components. Disposed rearwardly of the needlebar 22 is the usual presser foot bar 26 which carries the presser foot28 which coaets with a feed dog (not shown) in a usual fashion. Drive isimparted to a main drive shaft 20 from a drive motor 30 which isdisposed beneath the table or feed bed 14 (see FIGS. l and 2). The motoroutput shaft 30a carries a driving pulley 32 which is coupled by a belt34 to driven pulley 36 on the main drive shaft 20. As seen in FIG. l,the drive motor 30 is selectively coupled to and decoupled from thedriving pulley 32 by clutch 38 (shown in disengaged position) which isengaged and disengaged by a double arm clutch-actuating lever 40 pivotedon the motor housing at 42 by bracket 44. Arm 40a of theclutch-actuating lever 40 is bifurcated and engages a clutch actuatingpin 33a, and arm 40h is connected to the piston rod of a clutch-controlpiston and cylinder C5. The clutch-control piston and cylinder C5 is ofthe single acting springbiased type. Upon the introduction of air intothe cylinder, the piston rod is extended to rock the lever 40 in adirection to engage the clutch; and upon porting of the cylinder toatmosphere, the internal spring of the cylinder and piston C5 restoresthe clutch 38 to its disengaged position. Further description of theclutch control and the coordination of the stitching mechanisms by theusual sewing machine parts within the body 18 is dispensed with sincethese are well known to those skilled in the art.

Disposed rearwardly of the presser foot 28 is a rotary puller wheel 46which is arranged along the normal feed path of the material M throughthe sewing machine and directly behind the presser foot 28. The rotarypuller wheel 46 supplements the feeding action of the usual four-motionlfeed dog in the sewing machine which, for the present purposes, isusually insufficient to rapidly advance the material M past thestitching location afforded by the needle 24. The puller wheel 46 isconnected by an appropriate flexible coupling shaft 47 to a puller driveshaft 48 which is disposed rearwardly of the sewing apparatus and isjournalled on appropriate standards 50, 52. The puller drive shaft 48carries a relatively large diameter driven pulley 54 which is coupledvia belt 56 to a drive pulley 58 on the sewing machine main shaft 20.The drive pulley 58 may be of the adjustable diameter type to permitvariations in the drive from the main drive shaft 20 to the rotarypuller 46. For further details of this type of rotary feeder, referencemay be made to U.S. Patent No. 2,777,409 of Ian. 15, 1957 entitled FeedMeans for Sewing Machines.

Extending lfore and aft of the machine 10 is a conveyor 60 whichincludes plural side by side endless belts 62, 64, 66. The upper coursesof the belts 62, 64, 66 overlie the feed bed .14 and are arranged tounderlie the material M for advancing the same along a normal feed pathtoward the stitching location at the sewing machine 16. Thus, during atypical stitching interval, successive edge-adjacent portions of thematerial M are presented to the stitching mechanisms including theneedle 24 and the presser foot 2% at the stitching location for joinder.The endless belts of the conveyor 60 are trained over aligned pairs ofpulleys (i.e., pulleys 68, 70 for belt 66) which pulleys are securedrespectively to conveyor pulley shafts 72, 74 extending transversely ofthe machine. The shaft 72 is journalled on appropriate brackets (i.e.,bracket 76 depending from feed hed 14) at a location rearwardly of thesewing machine and receives drive from the motor 30 via worm 78 on shaftextension 72a which is coupled to worm gear Btl which in turn is drivenby bevel gear 82 on shaft 4S. Thus, upon rotation being imparted toshaft 48 for driving the puller wheel 46, corresponding rotary movementis imparted to the conveyor drive shaft 72 via gearing 82, 80, 78 toactivate the conveyor 60. It will be appreciated that the variable speedpulley 58 incorporated in the coupling arrangement to the sewing machinemotor 30 affords a convenient means for adjusting the rate of advance ofthe material M under the influence of the multiple belts 62, 64, 66 ofthe conveyor 60.

Overlying the feed bed or table 14 of the machine is a material-guidingassembly, generally designated :by the reference numeral 84, which isengageable with the material M and is operable to impart steering motionto such material as the same is advanced toward the stitching location.By displacing the material from side to side relative to the normal feedpath, it is possible to establish stitching along any requisite stitchline. A portion of a typical stitch line, designated by the numeral 86,is illustrated and is seen to be parallel to and spaced inwardly fromthe contoured edge e of the material M. The conveyor 60 serves toadvance the material M along a straight line feed path appropriate forstitching along and spaced inwardly of a material edge which is parallelto the linear feed established by the conveyor. However, the materialguiding assembly 84, which will now `be described, serves in conjunctionwith the conveyor 60 to steer the material M in a manner closelysimulating the guiding action imparted to the material under theinfluence by a machine operator when confronted with the problem ofstitching along a ocntoured or curved edge e, yet does so on anautomatic basis and to an order of accuracy and repeatability which isvirtually unobtainable by a machine operator.

The material guiding assembly 84 includes an elongated straight andsubstantially rigid guide rail or track 88 which projects forwardly fromthe stitching location and is intended to overlie the table 14 and theupper courses of the plural belts of the conveyor 60. The guide rail ortrack 88 is mounted on the support 12 for movement relative to thenormal feed path established by the plural belts of the conveyor 60. Inthis illustrative arrangement, the guide rail 88 is mounted for pivotalmovement about a vertical pivot and in a horizontal plane generallyspaced above the table 14. Specifically, appropriate bracketing 90 issecured to the machine body 18 to provide a vertical pivot in alignmentwith and rearwardly of the needle 24 (see FIG. l). The guide rail 88 issuspended above the feed bed 14 for side to side swinging movement aboutpivot 92 by an adjustable mounting arrangement which permits the rail tobe laterally adjusted relative to the -vertical pivot 92, for reasons tobe subsequently described. Specifically, the mounting arrangementincludes an L-shaped mounting bracket 94 which is appropriatelyconfigurated at one end to provide a support for the guide rail or track88 and is formed at its opposite end with a transverse mounting sleeve96 which is confined between two collars 98, 100 attached to a leadscrew 102. The lead screw 102 is received within an internally threadedsleeve 104 which in turn is journalled on the vertical pivot 92. Thelead screw 102 is manipulated by a knurled adjustment knob .106.Accordingly, upon turning of the adjustment knob y the lead screw 102may be threaded in and out relative to the sleeve 104 and the pivot 92to initially adjust the starting position for the guide rail 88.

Mounted on the guide rail or track 88 is a clamp assembly 108 whichincludes a spring-biased clamp which is adapted to engage the trailingend of' the material M along and spaced slightly inwardly of thecontoured edge e for the coordinate guiding function with the conveyor60. The clamp assembly 108 is seen to include a trolley or carriage 110which includes plural rollers 112:1, 11211, 112e engaging the upper andlower guiding surfaces of the track or rail 88. Depending from thetrolley 110` is a clamp-supporting bracket 114 which carries at itslower end a horizontally extending abutment plate 116 which is adaptedto be brought beneath the trailing end of the material M. Overyling theabutment plate 116 is a stripper plate 118 through which projects aclamping pin 120 which is mounted on a double arm clamp-supporting lever122 which is pivoted on bracket 114 at 124. Arm 122a extendssubstantially horizontally over stripper plate 118 and carries the clamppin 120 which extends through and engages the material M, while arm 122bextends generally upwardly and is connected to the plunger of aclampcontrol solenoid SL. A spring 126 is connected to arm 12211 and tobracket 114 to normally bias the clamp 120 into its operative ormaterial-engaging position. Solenoid SL is effective to overcome thebias of the spring and to urge the clamp 122 to a clearance positionenabling the trailing end of the material to be inserted within theclamp overlying the abutment 116 and in position for engagement by thepin at the start of a stitching interval or sequence and to be releasedat the end of the stitching interval.

In order to assure smooth operation of the clamp assembly 108 mountedvia trolley 110 on rail 88, provision is made for counterbalancing theclamp assembly such that the pulling force exerted by the puller roller46 and the usual feeding mechanisms in the sewing machine will permitthe unimpeded feed of the material M through the sewing machine forstitching. To this end, a counterweight 128 is provided beneath themachine which is connected via cable 130 and idler pulleys 132, 134, 136to the trolley 110 of the clamp assembly 108. By appropriate selectionof the weight 128, a rather delicately balance system can be establishedwhich will respond instaneously and which will not adversely effect thematerial (i.e., by stretching the same) notwithstanding the mass of theclamp assembly 108.

Provision is made for propelling the clamp assembly 108 along the guiderail 88 out of an adjustable starting position toward its finishingposition. Conversely, provision is made for propelling the clampassembly 180 back to the starting position at the end of the stitchinginterval and after the release of the material M by the clamp pin 120.Specifically a first clamp-propelling piston and cylinder C4 is disposedbehind the trolley 110, with the piston carrying an enlarged head 138which is arranged to engage and push the trolley 110 along the track 88toward the sewing machine 16. This piston and cylinder is adjustablymounted on the rail by the provision of a supporting shoe 140 which maybe fixed tothe rail by locking member 1-42. At the other end of theguide rail 88 forwardly of the sewing machine head 18 there is arrangeda second clamp-propelling cylinder and piston C3 which has an enlargedhead 144 in position to engage the trolley 110 and return the same tothe starting position upon the completion of the stitching interval, aswill be subsequently described.

Provision is made under the control of the machine operator forinitiating a stitching interval during which the clamp assembly 108moves from the adjusting position remote from the needle 24 to thefinishing position adjacent the needle. Further means including asignaling switch SS are provided which respond to the movement of theclamp assembly 108 into the finishing position for concluding thestitching interval. These controls will be described in conjunction withthe detailed description of FIGS. 3 to 5 inclusive.

The spring-biased presser foot 28 of the sewing machine normally isdisposed in its operative position but is held in an elevated positionfor the loading of the machine prior to the initiation of the stitchinginterval. This is accomplished by a piston and cylinder C1 which ismounted rearwardly of the sewing machine head (see FIGS. l and 2), withthe piston rod thereof coupled via linkage 146 to internal mechanisms onthe sewing machine which, upon operation of the piston and cylinder C1,lift the presser foot 28 to the elevated loading position.

Still further, a cutter 148 is disposed rearwardly the presser foot andthe puller wheel 46. The cutter 148 is mounted on a cutter mount 158pivoted on the bed plate at 152 and is movable at the end of a stitchinginterval from the retracted position illustrated in FIG. l to anoperative position directly behind the puller wheel 46, as indicated bythe directional arrows, for severing the stitching thread which normallyinterconnects successive completed stitch material assemblies. Thecutter 48 is moved from its normal inoperative position to the operativeposition under the control of the cutter-activating cylinder and pistonC2 at the end of the stitching interval at which time the presser footis raised to release the work.

Disposed forwardly of the needle 24 are a pair of spaced photocells P1,P2 which are mounted in a barrel rotatable about a vertical axis forpositioning thereof relative to the optimum line of advance of the edgee relative to the stitching mechanisms. As will be described, thephotocells P1, P2 serve to position the guide rail 88 to impart therequisite steering motion to the clamp assembly 108 during the stitchinginterval. Between the photocells P1, P2 and the needle 24 there isprovided in the feed bed of the machine two ports 154 which areconnected via flexible pipes 156 (see HG. 2) to an appropriate vacuumsource such that the material assembly is held down in critical locationin advance of the needle 24.

Provision is made for pivoting the guide rail 88 about its verticalpivotal mount 92 in accordance with the signals derived from thephotocells P1, P2 during the stitching interval and for manuallyadjusting the position of the guide rail 88 at the start of a stitchinginterval. These mechanisms are coordinated into the control illustratedin FIG. 3, with the control having the capability to sense the initialadjusted position of the guide rail S8 as established by the machineoperator and to restore the guide rail to such adjusted position at theend of each stitching interval. In this way, once the operatorestablishes the initial starting position for the guide rail for anyparticular stitching operation, the guide rail automatically is restoredto that initial starting position. Therefore, it is merely necessary toreload the equipment at the end of each stitching interval for the nextstitching operation, notwithstanding the fact that the rail has movedout of the requisite starting position during the stitching interval toimpart the necessary guiding action to the material assembly. Thisarrangement includes a double acting rail-adjusting cylinder and pistonC6 which is disposed beneath the feed bed of the machine and suspendedfrom the support 12 thereof at pivotal mount 158. The piston rod carriesa bifurcated yoke 160 which is coupled Via arm 162 to a vertical pivotshaft 164 which extends upwardly through the machine frame 12 to alocation above the work-supporting surface afforded by the feed bed 14.Arm 162 has a pivotal connection 166 to the yoke 169 on the piston rodat one end thereof, with the other end being rigidly connected to shaft164. Shaft 164 at its location above the feed bed carries a rigidsteering arm 163 which follows the motions imparted to arm 162 undercontrol of the cylinder and piston C6. Steering arm 16S has a pivotalconnection 170 at its end remote from shaft 164 to one end of a steeringlink 172 which has a pivotal connection 174 at its opposite end to railextension 88a. Rail extension 88a carries a supporting roller 176 whichrides upon the work-supporting surface 14. It will thus be appreciatedthat upon driving the piston toward the right in FIG. l, steering arm168 will be swung in a counterclockwise direction thereby swinging theguide rail 88 in the counterclockwise direction about its pivotal mount92. Conversely, upon driving the piston to the left in FIG. l, clockwisemotion will be imparted to the steering arm 16S, with a correspondingclockwise pivotal movement being imparted to the guide rail 8S. Air isintroduced into the opposite ends of the rail-adjusting cylinder andpiston C6 by the control, as will be described.

Manual adjustment of the position of the guide track or rail 88 isaccomplished by the provision of a track or rail positioner TP which isdisposed at a convenient location to one side of the machine and is seento include an adjustment handle 178 and a track position dial 180 havingtwo arcuate conductive segments TPa, TPa. The dial 18@ of the trackpositioner TP is journalled on an upstanding shaft 182. The adjustmenthandle 1'78 is tapped through the dial 1&0, and upon turning in theappropriate direction, permits the securement of the dial 180 in anyadjusted position on shaft 182. Journalled on the shaft 182 above thedisc 180 is a track positioner sprocket 184 which carries a contactorTPa which normally is intended to maintain a neutral position betweenthe conductor segments TPa and TPa, as shown mechanically in FIG. 1 anddiagrammatically in FIG. 3. However, as such times that contactor TPa ison one or the other of the conductive segments TPa, TPrz and the trackpositioner TP is in its operative mode, the control arrangement is suchas to restore the contactor to the neutral position with thecorresponding movement of the guide rail 88 to the adjusted positionestablished in the first instance by the rotational adjustment of thedial 180 of the track positioner TP under control of the operator.Sprocket 184 is coupled via chain 186 to driving sprocket 188 onintermediate shaft 164. Thus, the rotational movement imparted to theintermediate shaft 164 under control of the cylinder and piston C6 toachieve steering motion of the rail will be read into the trackpositioner TP via driving sprocket 188, chain 186 and driven sprocket184.

It may be desirable to supplement the holding effect of the vacuum ports154 by the provision of air jets directed downwardly on the material ata location overlying the vacuum ports 154. This may be accomplished bythe provision of two jet pipes 190 directed downwardly toward the ports154 which pipes are connected via conduit 192 to an appropriate sourceof air under pressure (i.e., a small blower).

Turning now specifically to FIG. 3, there is shown a typical control inschematic and diagrammatic form for use in connection with the presentapparatus. The various components of the machine which are integratedinto this control are shown schematically to facilitate an understandingof the operation of the control. The control includes main input lines192, 194 which are connected to an appropriate source of power over mainswitch MS in line 192. Associated with each of the several piston andcylinders are appropriate solenoid-controlled valvef for connecting therespective pnuematic actuating means t a source of air under pressurefor the related contro: functions. Specifically, solenoid control valveV1 connects the main air line 196 to both the cylinder and piston C1 forthe presser foot 28 and the cylinder and piston C2 for the cutter 46. V1is energized over nominally closed contact Ria of a delay action relayR1 which has its energization coil connected across the lines overcontacts R2a, R2a of relay RZ. Relay R2 in turn has its energizationcoil connected across the lines of a first foot control switch PS1 andinterval-end or stop switch SS. In the rest position of the equipment,presser foot 28 is held in its elevated position by activation ofcylinder C1 and correspondingly the cutter 46 is held in its operativeposition by its cylinder C2. Upon opening of contact Rla in response toenergization of relay R1 under control of relay R2, the presser foot 28moves into its operative position and the cutter 46 moves into aretracted or clearance position.

Relay R2 includes contact R2a which transfers onto contact R2a tocondition the energization circuit for relay R3 over a second footcontrol switch PS2. Relay R2 includes a holding contact R211 which isclosed upon energization of the relay R2 under control of the first footcontrol switch FSI to enable the machine operator to remove his footfrom switch F81 after initiating the first sequence of operations, towit, the dropping of the presser foot 28 into the operative position andthe movement of the cutter 46 away from the stitch path. Relay R3, whichis energized in response to closing of the second foot control switchPS2, includes a first contact R3a which is normally against contact R3abut is transferred onto contact R3a. In the rest position of theequipment, contact R3a completes an energization circuit for thesolenoid SL which normally maintains the clamp pin 124i in its retractedposition. Relay R3 includes holding contact Rb to complete a holdingcircuit therefore which enables the operator to remove his foot fromswitch FS2 after initiating this phase of the operation. Thus, after theoperator has depressed foot switch FSI to clamp the lpresser footagainst the work load therebeneath, the operator then appropriatelypositions the material assembly relative to the clamp 120 and depressesfoot switch FSZ to complete the clamping of the fabric. Transfer ofcontact R3a from contact R3a' restores the clamp-return cylinder C3which is activated over solenoidcontrolled valve V2. The establishmentof the circuit over contact R3a, R3a operates solenoid-controlled valveV3 which actuates the clutch control C and the clamp starting cylinderC4.

Closing of the second foot switch F82, which signals the beginning of astitching interval, energizes relay R4 which transfers the contactsthereof to disable the track positioner TP and establishes the requiredContact to place the rail-adjusting cylinder C6 under control of thephotocells P1, P2.

Turning now to the track selector TP, as previously described theadjustable dial 18() has two conductive segments TPa', TPa" which areengaged by contacter or slider TPa, with the movement of the contactorbeing linked to the movement of the guide track 88. Contacter TPtz isnormally connected over contact R4a, R4cz of relay R4 to line X of relayA1 having normally closed contact Ala. The photocell P1 is seenconnected to relay A1 at line X and is connected to line X over contactR4a" of relay R4. Thus, in the illustrated position, relay A1 is undercontrol of the contactor TPa of the track positioner TP. Upon transferof con-tact R411 against contact R4a in response to energization of therelay R4, the track positioner TP is `disabled and the photocell P1serves as the input to relay A1. When contactor TPa is on conductivesegment TPcz', line X and X are connected to each other to activaterelay A. However, upon transfer of Contact R4a into engagement withcontact R4a, photocell P1 takes over and when exposed to lightcomple-tes a circuit across lines X, X to activate relay A1. In asimilar fashion, relay A2 is under control of the track positioner TPvia segment Tla" and photocell P2. Relay A2 includes a first contact A2@which is normally closed and establishes an energization circuit forsolenoid-controlled valve t V5 over contacter R411' or relay R4. RelayA2 further includes contact A2Z) which is normally open and uponenergization of the relay establishes a secondary energization circuitfor solenoid-controlled valve V5 over contact 44b, R4b" of relay R4, thelatter being energized to disable the track positioner TP. In theillustrated position, track positioner TP establishes a circuit acrosslines Y, Y at such time as contactor TPa is on conductive segment TPa todisrupt the energization circuit for solenoidcontrolled valve V5 andthereby bleed off port the corresponding right side of therail-adjusting cylinder and piston C6. By way of summary, when the trackpositioner TP is in control (relay R4 deenergized), the rail-adjustingcylinder and piston C6 is appropriately ported to atmosphere andactivated by solenoid-controlled valves V4, V5 to restore the contactorTPa to the neutral position illustrated in FIG. 3. This may beappreciated by reference to FIG. 5 wherein a typical position ofcontactor TPcz on segment TPa" is illustrated, it being noted that therelay R4 is not energized such that the track positioner TP is incontrol of the rail-adjusting cylinder and piston C6. For thisillustrated condition, a circuit is established to cross the lines Y, Y-transferring the contacts of relay A2 to disrupt the energizationcircuit for solenoid-controlled valve V5 over open contact A2a. Closingof contract A2b has no effect since relay F4 has not been energized.Energization of solenoid-controlled valve V5 bleeds the right end of thecylinder C6. Input is imparted to the left end of cylinder C6 viasolenoid-controlled valve V4 which is energized over closed contact Ala.Accordingly, the rail-adjusting cylinder and piston C6 is activateduntil such time as the contactor TPa, which is ganged to the linkageassociated with the guide rail 88, assumes the neutral positionillustrated in FIG. 3 whereupon the connection across the energizingcontacts of relay A2 is opened and the relay restores to the illustratedposition in FIG. 3.

In FIG. 4, there is shown a typical running condition for the apparatuswherein relay R4 has been energized to transfer its contact R4H, R46such that the relays A1, A2 are placed under direct control of thephotocells P1, P2. For the illustrated condition, it -will be noted thatfabric is removed from photocell P2 thereby signalling relay A2 toactivate the contacts thereof which is effective to establish anenergization circuit for solenoid-controlled valve V5 over contactsR417, R4b. Since fabric overlies photocell P1, contact Ala remainsclosed and solenoid-controlled valve V4 remains energized. For allpractical intents and purpose, the rail-actuating piston and cylinder C6signals that the operation is proceeding properly and that guide track`88 does not have to be ydisplaced (see the condition illustrated inFIG. l wherein photocell P1 is co-vered by the material M whilephotocell P2 is exposed signalling the proper feed of the particularassembly M to the stitching location). At such time as photocell P1 isexposed to light, indicating that the edge e has gone too far to theleft off of the stitching path (when viewed from the right in FIG. l),relay A1 is activated to open contact Ala which energizessolenoid-controlled valve V4 to port the corresponding side of thecylinder C6 to atmosphere, with the other side being connected to airunder pressure. This obviously brings about a corresponding restorationof the edge e of the material M to the proper feeding position relativeto the needle 24. If the material shifts to far to the right blockingboth photocells P1, P2, relay A2 transfers to interrupt the energizationcircuit for solenoid-controlled valve V5. With the continued applicationof pressure over solenoid-controlled valve V4 to the opposite side ofthe cylinder C6, the corresponding correction is imparted to the guidetrack 88 until such time as the edge is restored to the proper positionfor stitching.

A typical sequence of operation will now be described in detail tofacilitate a more thorough understanding of the present invention:

At the start of the operation, the operator places the material M ontothe feed bed of the machine overlying the conveyor and places theleading end of the assembly beneath the presser foot 28. The presserfoot is elevated to its inoperative position under control of cylinderC1 and the cutter 46 is along the stitch line having just cut theprevious fabric assembly. The operator then adjusts the clam-p assembly108 along the guide track 88 to a position wherein the clamp pin 120 isengaged with the trailing end of the contoured edge e. Based upon amodest amount of experience, the operator will determine whether or notthe lateral position of the guide track 88 should be adjusted relativeto the stitchingtlocation by turning knob 106 to assure that thematerial M will not have to make too radical an excursion as it is fedthrough the sewing machine 1'6. Thereupon, the operator depresses footcontrol FSI which actuates relay R2 which in turn deenergizes relay R1.Energization of relay R2 under the moment-ary control of the foot switchFSl completes a holding circuit. Deenergization of relay R1 allows thepresser foot 28 to move against the work to clamp the same and retractsthe cutter disc 46 from the `stitch path until the end of the machinecycle. Thereupon, the operator depresses foot switch -FSZ which acttivates relay R3. Transfer of contact R3a causes clamp pin 120 to engagethe trailing end of the work in response to deenergization of itssolenoid SL and to also activate solenoid-controlled valve V3 whichengages the clutch associated with the sewing machine motor 30 andactivates the clamp-propelling cylinder and piston C4 to overcome theinertia of the system and start the clamp assembly 108 down the guidetrack 88. The presser foot 24 and rotary puller 46 are eifective toadvance the work through the stitching location, with the trailing endthereof being steered under control of the guide rail 88 and thephotocell controls P1, P2 as previously described. The closing of footswitch FSZ energizes relay R4 which transfers its contacts to disablethe track positioner TP and places the rail-adjusting cylinder andpiston C6 under direct control of the photocells P1, P2 for thecontinuous monitoring of the position of the edge e of the material M,'as previously described in conjunction with FIG. 4. Periodically, oneside or the other of the cylinder C6 is ported to atmosphere, with theother side being connected under pressure to establish new adjustedpositions for the guide track 88 as the edge e of the material isconstantly monitored in advance of the stitching location. At the end ofthe run, the clamp assembly 108 contacts the stop switch SS whichdisrupts the holding circuit for relay R3 -by opening the holdingcircuit established over contact R315. Transfer of relay R3 to theposition illustrated in FIG. 3 disrupts the energization circuit forsolenoid-controlled valve V3 which releases the clutch associated withmotor 30 and permits the internal spring within the clamp-startingcylinder C4 to restore the same to the illustrated starting position.Also, opening of stop switch SS opens the energization circuit for relayR4 which once again places the system under control of the trackpositioner TP which simultaneously reestablishes the initial adjustedposition for the guide track as set in the irst instance by theadjustment of dial 180. For example, as described in conjunction withFIG. 5, the contactor TPa may be on segment TPa when the end of thestitching interval is signaled by stop switch SS and the deenergizationof relay vR4 will thereby bring about the repositioning of the guidetrack to the requisite starting position. Transfer of Contact Ra ofrelay R3 against contact R3a energizes the solenoid controlled valvelifting clamp pin 120 and simultaneously sends the clamp assembly 108back to the adjusted starting position by activation of the Clamp-returncylinder and piston C3.

Although the opening of stop switch SS also disrupts the holding circuitover contact RZb for relay -RZ transferring its contacts to complete theenergization circuit for relay R1, the time delay of relay R1 is suchthat Contact Rla will remain open for a time which, although relativelyshort, is sufficient to allow the end of the fabric to pass thestitching location. There is suiiicient inertia in the drive of thesewing machine 16 to continue feed via the feed dog thereof and thesupplemental rotary puller 46, notwithstanding the release of the clutch38. As a final step, in response to closing of contact Ria, presser foot28 is lifted to the elevated position and cutter disc 46 is swung overthe trailing threads of the completed assembly to cut such threads.

The sequence is completed runder control of the track positioner TP inresponse to deener-gization of relay R4 which restores the guide trackS8 to the initial adposition whereupon the operator loads the next Pieceor fabric assembly into the equipment. At the end of any givenproduction run, it is a relatively simple matter to make the necessaryreadj-ustments to accommodate the next stitching pattern.

What I claim is:

1. A machine for stitching material along a prescribed stitch linecoextensive with and spaced inwardly from an edge thereof comprising asupport, sewing mechanisms on said support including a reciprocatingneedle operable at a stitching location for successively stitching saidmaterial along said prescribed stitch line, said material being arrangedforwardly of said stitching location and advanced toward and throughsaid stitching location along a normal feed path relative to saidneedle, guide means engageable with said material and operable to impartsteering motion to said material as the same is advanced toward saidstitching location for displacing said material from side to siderelative to said normal feed path such that said material will bestitched substantially along said stitch line, said guide meansincluding an elongated guide rail projecting forwardly of said needleand a clamp movably mounted on and guided by said rail, means mountingsaid guide rail on said support for movement relative to said normalfeed path, said clamp being engageable with said material contiguous tothe trailing end of said edge when the leading end of said edge isinitially positioned at said stitching location, means responsive todeviations of said edge relative to said normal feed path for movingsaid guide rail in a direction to restore said edge, said guide railbeing effective in response to its movement to impart steering motion tosaid clamp as the latter is moved therealong and toward said stitchinglocation to continuously orient and present successive edgeadjacentportions of said material in relation to said sewing mechanisms at saidstitching location for stitching along said prescribed stitch line.

2. A machine according to claim 1 including materialadvancing meansengageable with said material for transporting the same through andbeyond said stitching location.

3. A machine according to claim 1 wherein said elongated guide rail isrigid and including means for pivotally mounting said guide rail on saidsupport.

4. A machine according to claim 1 including control means for movingsaid rail relative to said normal feed path and having a pair ofphotocells disposed contiguous to said needle and at opposite sides ofsaid normal feed path for sensing deviations of said edge.

5. A machine according to claim 4 including means responsive to andunder control of said photocells for positioning said guide rail toimpart the requisite steering motion to said clamp.

6. A machine according to claim 1 including means under control of themachine operator for initiating a stitching interval during which saidclamp moves from an adjustable starting position remote from said needleto a finishing position adjacent said needle and means responsive tomovement of said clamp to said finishing position for concluding saidstitching interval.

7. A machine according to claim 6 wherein said sewing mechanismsincluding a spring biased presser foot and means for holding saidpresser foot in an elevated position until the initiation of saidstitching interval.

8. A machine according to claim 6 including a cutter positioned behindsaid needle for severing stitching threads which normally interconnectcompleted stitched material assemblies.

9. A machine according to claim 6 including means operable in responseto the initiation of said stitching interval to propel said clamp alongsaid guide rail out of said adjustable starting position toward saidiinishing position.

10. A machine according to claim 6 including means operable at the endof said stitching interval for disengaging said clamp from saidmaterial.

11. A machine according to claim 6 including means operable when saidmaterial clamp is in said finishing position and after release thereoffrom said material to propel said clamp back toward said startingposition.

12. A guiding mechanism for advancing material to a work location whilecontinuously orienting said material in accordance with the contour ofan edge thereof comprising an elongated guide member extending towardsaid work location, means for mounting said guide member for movementrelative to said work location, a follower engaging said guide memberand movable therealong and clamp means operatively connected to saidfollower and engageable with said material such that the latter isguided in response to movement of said follower along Said guide memberas the latter moves relative to said work location.

13. A guiding mechanism according to claim 12 including means for movingsaid follower along said guide member toward said work location.

14. A guiding mechanism according to claim 12 including a conveyorarranged to underlie and engage said material and to advance the samealong a feed path toward said work location.

15. A machine for stitching material along a prescribed stitch linecomprising sewing mechanisms at a stitching location for successivelystitching said material along said prescribed stitch line, said materialbeing arranged forwardly of said stitching location and advanced towardand through said sewing mechanisms along a normal feed path relativethereto, guide means engageable with said material and operable toimpart steering motion to said material as the same is advanced towardsaid sewing mechanisms for displacing said material relative to saidnormal feed path such that said material will be stitched substantiallyalong said stitch line, said guide means including a cam member and afollower movably mounted on and guided by said cam member, meansmounting said cam member for movement relative to said normal feed path,said follower being engageable with said material contiguous to thetrailing end of said edge when the leading end of said edge is initiallypositioned in operative relation to said stitching mechanisms, meansresponsive to deviations of said edge relative to said normal feed pathfor moving said cam member in a direction to restore said edge, said cammember being effective in response to its movement to impart steeringmotion to said follower as the latter is moved therealong and towardsaid stitching mechanism.

16. A machine according to claim 15 including material-advancing meansengageable with said material for transporting the same through andbeyond said stitching location.

17. A machine according to claim 15 wherein said cam member is anelongated guide rail and including means for pivotally mounting saidguide rail.

18. A machine for stitching material along a prescribed stitch line inrelation to an edge thereof comprising a support, sewing mechanisms onsaid support operable at a stitching location for successively stitchingsaid material along said prescribed stitch line, said material beingarranged forwardly of said stitching location and advanced toward andthrough said stitching location along a normal feed path relative tosaid needle, mov- Cil able guide means engageable with said material andoperable to impart steering motion to said material at the same isadvanced toward said stitching location for displacing said materialrelative to said normal feed path such that said material will bestitched substantially along said stitch line, said guide means beingengageable with said material contiguous to the trailing end of saidedge when the leading end of said edge is initially positioned at saidstitching location, means responsive to deviations of said edge relativeto said normal feed path for moving said guide means in a direction torestore said edge, said guide means being effective in response to itsmovement to impart steering motions to said material as it moves towardsaid stitching location to continuously orient and properly presentsuccessive edge-adjacent portions of said material in relation to saidsewing mechanisms.

19. A machine according to claim 18 including means for mounting saidguide means for movement in relation to said normal feed path such thatsaid guide means may be adjustable before initiating a stitchinginterval.

20. A machine according to claim 19 including means operable at the endof said stitching interval for restoring said guide means to theadjusted initial position.

21. A machine according to claim 20 wherein said guide means includes anelongated pivoted guide rail projecting forward of said sewingmechanisms and a clamp movably mounted on and guided by said guide railand movable toward said stitching location during said stitchinginterval.

22. A machine according to claim 21 including control means for movingsaid guide means relative to said normal feed path, said control meansincluding photocells positioned in relation to said normal feed path forsensing devilations of said edge in relation to said normal feed pat 23.A machine according to claim 18 including vacuum means disposed adjacentsaid normal feed path for positioning said material for operationthereon of said sewing mechanisms.

References Cited UNITED STATES PATENTS 1,646,129 10/ 1927 Wagner.1,942,128 1/1934 Sommer. 2,290,123 7/ 1942 Wilfong 112-203 2,679,6205/1954 Berry 1l21024 XR 3,072,081 1/1963 Milligan et al. 3,182,6195/1965 Sally 112--153 XR JAMES R. BOLER, Primary Examiner.

U.S. Cl. X.R.

1. A MACHINE FOR STITCHING MATERIAL ALONG A PRESCRIBED STITCH LINE COEXTENSIVE WITH AND SPACED INWARDLY FROM AN EDGE THEREOF COMPRISING A SUPPORT, SEWING MECHANISMS ON SAID SUPPORT INCLUDING A RECIPROCATING NEEDLE OPERABLE AT A STITCHING LOCATION FOR SUCCESSIVELY STITCHING SAID MATERIAL ALONG SAID PRESCRIBED STITCH LINE, SAID MATERIAL BEING ARRANGED FORWARDLY OF SAID STITCHING LOCATION AND ADVANCED TOWARD AND THROUGH SAID STITCHING LOCATION ALONG A NORMAL FEED PATH RELATIVE TO SAID NEEDLE, GUIDE MEANS ENGAGEABLE WITH SAID MATERIAL AND OPERABLE TO IMPART ENGAGEABLE WITH SAID MATERIAL AS THE SAME IS ADVANCED TOWARD SAID STITICHING LOCATION FOR DISPLACING SAID MATERIAL FROM SIDE TO SIDE RELATIVE TO SAID NORMAL FEED PATH SUCH THAT SAID MATERIAL WILL BE STITCHED SUBSTANTIALLY ALONG SAID STITCH LINE, SAID GUIDE MEANS INCLUDING AN ELONGGATED GUIDE RAIL PROJECTING FORWARDLY OF SAID NEEDLE AND A CLAMP MOVABLY MOUNTED ON AND GUIDED BY SAID RAIL, MEANS MOUNTING SAID GUIDE RAIL ON SAID SUPPORT OR MOVEMENT RELATIVE TO SAID NORMAL FEED PATH, SAID CLAMP BEING ENGAGEABLE WITH SAID MATERIAL CONTIGUOUS TO THE TRAILING END OF SAID EDGE WHEN THE LEADING END OF SAID EDGE IS INITIALLY POSITIONED AT SAID STITCHING LOCATIN, MEANS RESPONSIVE TO DEVIATIONS OF SAID EDGE RELATIVE TO SAID NORMAL FEED PATH FOR MOVING SAID GUIDE RAIL IN A DIRECTION TO RESTORE SAID EDGE, SAID GUIDE RAIL BEING EFFECTIVE IN RESPONSE TO ITS MOVEMENT TO IMPART STEERING MOTION TO SAID CLAMP AS THE LATTER IS MOVED THEREALONG AND TOWARD SAID STITCHING LOCATION TO CONTINUOUSLY ORIENT AND PRESENT SUCCESSIVE EDGEADJACENT PORTIONS OF SAID MATERIAL IN RELATION TO SAID SEWING MECHANISMS AT SAID STITCHING LOCATION FOR STITCHING ALONG SAID PRESCRIBED STITCH LINE. 